Field
Embodiments described herein relate to electronic packaging. More particularly, embodiments relate to packaging techniques for providing electro-magnetic interference (EMI) shielding.
Background Information
Plastic ball grid array (BGA) substrates are commonly used for memory, controller, and chipset applications amongst others. BGA substrates are commonly sold in the strip form, and including one or more build-up layers, and optionally a core. A common BGA package assembly process may include using an off-the shelf BGA substrate strip, mounting a plurality of die and components onto the BGA substrate strip, and encapsulating the plurality of die and components in a molding compound on the BGA strip. A plurality of packages may then be singulated from the molded BGA substrate strip.
In some applications, electro-magnetic interference (EMI) shielding is formed on the singulated packages in order to either mitigate EMI radiation from the package or to prevent EMI radiation from external sources from interfering with operation of the package. In one implementation an EMI shielding layer is formed over the molding compound and side surfaces of the singulated BGA substrate so that the EMI shielding layer is in direct contact with an exposed ground wire within the BGA substrate. If the electrical connection between the EMI shielding layer and the exposed ground wire is defective, the EMI shielding effect may not be achieved.